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991.
Based on the eigensystem {λj,φj}of -Δ, the multiple solutions for nonlinear problem Δu f(u) =0 in Ω, u=0 on Ω are approximated. A new search-extension method (SEM), which consists of three steps in three level subspaces, is proposed. Numerical simulations for several typical nonlinear cases, i.e. f(u) = u~3,u~2(u-p),u~2(u~2 -p), 相似文献
992.
The bifurcation instability problem for cylindrical shells made of particulate composites with nonlinear elastic matrix and
damaged inclusions is formulated and solved
__________
Translated from Prikladnaya Mekhanika, Vol. 43, No. 8, pp. 80–91, August 2007. 相似文献
993.
Silvia Bonettini Valeria Ruggiero Federica Tinti 《Numerical Linear Algebra with Applications》2007,14(10):807-831
This work is concerned with the convergence properties and the numerical analysis of the preconditioned conjugate gradient (PCG) method applied to the solution of indefinite linear systems arising in nonlinear optimization. Our approach is based on the choice of quasidefinite preconditioners and of a suitable factorization routine. Some theoretical and numerical results about these preconditioners are obtained. Furthermore, we show the behaviour of the PCG method for different formulations of the indefinite system and we compare the effectiveness of the proposed variants. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
994.
本文提出一种氟电极测铝的新方法,即二次回归校正曲线法及分段抛物插值法。由于汇集了1.该法依据的数学模型与实验数据相符;2.AppleⅡ-ISE智能离子计具有较强的数据处理功能;3.氟电极性能良好等三个特点,故本法准确可靠,快速方便,具有一定理论意义和较大实用价值。 相似文献
995.
Zhi-Chi Zhu 《Acta Mechanica Solida Sinica》1990,3(4):457-468
Researches on sound propagation problems in ducts done by the author and other investigators in recent years are briefly discussed in this paper. The finite difference method used in fluid mechanics is used for solving these problems thus presenting an aspect of the development of research work in this field at home and abroad.The project supported by National Natural Science Foundation of China. 相似文献
996.
S. Lucidi 《Journal of Optimization Theory and Applications》1990,67(2):227-245
An algorithm for nonlinear programming problems with equality constraints is presented which is globally and superlinearly convergent. The algorithm employs a recursive quadratic programming scheme to obtain a search direction and uses a differentiable exact augmented Lagrangian as line search function to determine the steplength along this direction. It incorporates an automatic adjustment rule for the selection of the penalty parameter and avoids the need to evaluate second-order derivatives of the problem functions. Some numerical results are reported. 相似文献
997.
Solution differentiability for variational inequalities 总被引:1,自引:0,他引:1
Jerzy Kyparisis 《Mathematical Programming》1990,48(1-3):285-301
In this paper we study solution differentiability properties for variational inequalities. We characterize Fréchet differentiability of perturbed solutions to parametric variational inequality problems defined on polyhedral sets. Our result extends the recent result of Pang and it directly specializes to nonlinear complementarity problems, variational inequality problems defined on perturbed sets and to nonlinear programming problems. 相似文献
998.
非线性灰色微分方程(dx)/(dt)+ax~(■a)=b 的拟合 总被引:3,自引:0,他引:3
本文给出了拟合非线性灰色微分方程 dx/dt+ax~(■a)=b 的计算方法,并讨论了它的性质及应用. 相似文献
999.
M. Palese 《Theoretical and Mathematical Physics》2005,144(1):1014-1021
We solve the Backlund problem for both the compact and noncompact versions of the Ishimori (2+1)-dimensional nonlinear spin model. In particular, we realize the arising Backlund algebra in the form of an infinite-dimensional loop Lie algebra of the Kac-Moody type.This note is part of joint research work with E. Winterroth.__________Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 144, No. 1, pp. 153–161, July, 2005. 相似文献
1000.
T. Fiedler B. Sturm A. Öchsner J. Gracio G. Kühn 《Mechanics of Composite Materials》2006,42(6):559-570
The mechanical properties of periodic hollow-sphere structures are investigated numerically. Young’s modulus and the Poisson
ratio are determined in order to describe their linearly elastic behaviour. The initial compressive yield strength is also
calculated. The spheres are located at the nodes of a cubic primitive lattice. The cohesion is achieved by an adhesive concentrated
in the minimum gap between neighbouring spheres. The geometry of the structure is discretized based on regular hexahedral
elements. This approach is much more time-consuming, but it is important in order to achieve a more accurate simulation of
the nonlinear behaviour (e.g., plasticity) of such materials.
Russian translation published in Mekhanika Kompozitnykh Materialov, Vol. 42, No. 6, pp. 803–816, November–December, 2006. 相似文献